Methane accounts for more than one-quarter of the anthropogenic radiative imbalance since the pre-industrial age. Its largest sources include both natural and human-mediated pathways: wetlands, fossil fuels (oil/gas and coal), agriculture (livestock and rice cultivation), landfills, and fires. The dominant loss of methane is through oxidation in the atmosphere via the hydroxyl radical (OH). Apart from its radiative effects, methane impacts background tropospheric ozone levels, the oxidative capacity of the atmosphere, and stratospheric water vapor. As such, changes in the abundance of atmospheric methane can have profound impacts on the future state of our climate.

Sun-bleached skeletons of long-dead whitebark pine trees stand at the top of a 7,200-foot-high ridge along the Reservation Divide on the Flathead Indian Reservation, Montana. With annual average temperatures in Montana rising, the whitebark pine that were not previously threatened are now facing an increase in blister rust infections, mountain pine beetle infestations and wildfire.

Stretching from British Columbia, Canada down to parts of California and east to Montana, live the whitebark pine. The tree grows in subalpine and timberline zones — elevations anywhere from 4,000 to almost 9,000 ft. It's an unforgiving space. The wind is harsh. Plants and animals confront sub-freezing temperatures, often until summertime.

The whitebark pine has historically thrived in these lands. But today, the tree species is in trouble. So much so that the U.S. Fish and Wildlife Service listed the whitebark pine as a threatened species in December 2022. Increased fire intensity from climate change and colonial fire suppression practices, infestation by mountain pine beetles and a deadly fungus called blister rust — they're collectively killing this tree.

Five times in our planet's history, adverse conditions have extinguished most of life.

Now, scientists say, life on Earth could be in trouble again, with some even saying we could be entering a sixth mass extinction.

No credible scientist disputes that we are in a crisis regarding the speed at which nature is being destroyed.

But could we really be on track to lose most life on Earth?

Human-caused climate change, changes in land use and pollution are rapidly transforming the planet, making it harder for species to adapt and survive.

Reverse nature's decline or there is no future - UN

The United Nations' biodiversity chief says global talks under way in Montreal are the "last chance" to reverse the destruction of the natural world.

"Biodiversity is the foundation of life. Without it, there is no life," Elizabeth Maruma Mrema stated.

But she is worried about the amount of work still needed for the 196 countries to reach an agreement.